From which day does the number of weeks of pregnancy begin?

After pregnancy, women normally need to calculate gestational weeks according to the time of menstrual cessation of women, and the number of weeks of pregnancy is calculated from the first day of the last menstrual period of women. Normally, 7 days is a gestational week, and 4 gestational weeks is a gestational month. Most women are full term after 37 weeks of pregnancy and may exhibit parturient episodes at any time and deliver the fetus, so regular contractions after 37 weeks of pregnancy require hospitalization for delivery.